In continuation of research done during the preceding year the main objectives during the second year of the grant will be (1) the completion of the characterization of human liver prenyl transferase (farnesyl pyrophosphate synthetase) and its comparison with the similar enzyme from other animal sources; (2) the examination of the nature of hypecholesterolemia induced in rabbits immunized with pig-liver prenyl transferase; (3) study of mevalonate metabolism in experimental animals (extension of studies on the non-sterol, "shunt," pathway of mevalonate metabolism and effects of chronic administration of mevalonate). The project as a whole in subsequent years involves also the further synthesis of potential inhibitors of prenyl transferase and the study of squalene synthetase in liver.